Morphological changes of the intrinsic cardiac nervous system in experimental models of right ventricular hypertrophy.

Abstract

It was characterized the morphological changes of the intrinsic cardiac nervous system (ICNS) in two experimental models of right ventricular hypertrophy (RVH) in rats through Golgi‐Cox and Glyoxylic acid methods. Male Sprague dawley rats were used. RVH was induced with monocrotaline, and carbon tetrachloride (CCl4). After 3 and 8 weeks respectively, systolic right ventricular pressure (SRVP) was recorded and after hearts were extracted, washed, and incubated for 30 days in Golgi Cox solution, sectioned by vibrotome, processed and analyzed by the Sholl method under light microscopy adapted to a camera lucida. Diameters of ganglion and nerve fiber from right ventricle were recorded in microns. Histofluorescence for catecholamine was made and analyzed qualitatively. In both experimental groups increases in SRVP and RVH were confirmed, however mortality was higher in monocrotaline group. In heart from CCl4 rat, we found clearly increased in number and size of ganglion and nerve fibers in the right ventricle, however in hearts from monocrotaline rats a decrease in number and size of ganglion were found. The results were confirmed with the histofluorescence for catecholamine. Ours results show that there is a different impact in the ICNS, related to pathologic mechanism involved in RVH, suggesting that the repercussion on the ICNS could determine the development of heart failure and mortality